Elec-tric-ity, Eeeee-lec-tricity!
Dec. 3rd, 2004 05:48 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
ninevirtuesStep 1: Measure J, the lab partner. Mark a spot 3 cm to the right of his belly button, 15 cm right of his belly button, and 3 cm below and right of his costosternal junction. Clean those spots with alcohol. Re-mark them with ballpoint pen, because alcohol has removed the pen mark.
Step 2: Place electrodes on either side of said spots. (The object was to measure the electrical activity of the rectus abdominis (upper and lower) and the external obliques.)
Step 3: Place ground electrode on bony part of elbow.
Step 4: Fire up the machine and test for signal. Discover there is no signal in the third lead. Troubleshoot the leads (thanks J) and discover there is no connection for the third one. Add it, test again. Hooray, now an abdominal crunch produces a clear effect on all three data inputs.
Step 5: Fire up the machine; J does ten crunches, ten oblique crunches, and ten of the berserk abdominal exercise we are testing which involves blowing up a balloon while doing a pelvic tilt. (Really!)
Result: Beautiful. You could clearly see the muscle contraction involved when he did a repetition of each exercise. He set up his camera, and we took pictures of him crunching for the poster we plan to do.
Then it was my turn: We hooked me up to the machine, and I did ten crunches, ten oblique crunches, ten of the berserk exercise. All was well.... except for the tiny spike in the data collection that repeated at suspiciously regular intervals.
It was my heartbeat, which the electrodes picked up from my abdominal aorta. (!) We will have to perform some fancy data smoothing to remove it.
In any case, we got the machine to work. We have more people recruited to come and be test subjects on Sunday. Even if we can't arrange that, we do have pilot data from the two of us. Hooray!
Step 2: Place electrodes on either side of said spots. (The object was to measure the electrical activity of the rectus abdominis (upper and lower) and the external obliques.)
Step 3: Place ground electrode on bony part of elbow.
Step 4: Fire up the machine and test for signal. Discover there is no signal in the third lead. Troubleshoot the leads (thanks J) and discover there is no connection for the third one. Add it, test again. Hooray, now an abdominal crunch produces a clear effect on all three data inputs.
Step 5: Fire up the machine; J does ten crunches, ten oblique crunches, and ten of the berserk abdominal exercise we are testing which involves blowing up a balloon while doing a pelvic tilt. (Really!)
Result: Beautiful. You could clearly see the muscle contraction involved when he did a repetition of each exercise. He set up his camera, and we took pictures of him crunching for the poster we plan to do.
Then it was my turn: We hooked me up to the machine, and I did ten crunches, ten oblique crunches, ten of the berserk exercise. All was well.... except for the tiny spike in the data collection that repeated at suspiciously regular intervals.
It was my heartbeat, which the electrodes picked up from my abdominal aorta. (!) We will have to perform some fancy data smoothing to remove it.
In any case, we got the machine to work. We have more people recruited to come and be test subjects on Sunday. Even if we can't arrange that, we do have pilot data from the two of us. Hooray!
